I saw the Oaxis InkCase at the Mobile World Congress last week, and it looks pretty neat. The v2 “case” is actually an e-ink panel that connects to the iPhone (or other device) via Bluetooth and can show anything on its e-ink screen. The new version is modular, so you can slip in into any case for any device, and even mount it, say, on the handlebars of a bike for a sunlight-friendly readout.

The old InkCase was an e-ink screen on the back of your phone case, meaning it fit one device only. But freeing it from the case doesn’t just make it future-proof and cheaper to manufacture. It also makes it more useful. I can think of a ton of times that I’d like to use my iPhone but not burn its display or even remove it from the safety of my pocket.

You could use the screen for reading in sunlight, of course (the InkCase has three buttons on the front for remote control), but also for following maps, as a bike/sports computer, as a direction-giving HUD in the car, or just as a shopping list. In short, any time you’d prefer to keep the screen on, or to use your iPhone in the sun. And if you use it with the iPad you get many of the advantages of a smaller device in your pocket.

The current, last-gen InkCase is still on sale for $129. Hopefully the new one will be along soon.